Evaluation of Cell Mediated Immunity following Rubella Vaccination Using Lymphocyte Proliferation

Background and Aims: Rubella is predominantly a childhood disease that is endemic throughout the world and when rubella outbreaks occur, they are accompanied by birth defects following congenital rubella syndrome. Immunity to rubella virus as a teratogenic agent has an important role for prevention of these serious congenital defects. Lymphocyte proliferation assay is a way for investigation of human cell-immunity and its ability against rubella infection. Materials and Methods: The blood samples were obtained in sodium heparin tubes. Ficoll was added to separate lymphocytes. The cells were cultured with RPMI 1640 medium with 15% calf serum in microplates and incubating at 37°C in 3-5% CO2. Mitogens including Phytohemagglutinin and rubella hemagglutinin antigen (derived Takahashi strain) were added, separately. Then a fluorescent nucleotide was added. On day 10th-11th the wells stained and observed. Results: Lymphocytes stimulated with the mitogens were observed directly with an inverted microscope. Their aggregation and growth were detected after two days. Also lymph proliferation was shown using labeled nucleotide comprising a new fluorophore, by fluorescent microscopy. Response to full particle of attenuated virus was better than antigens derived from different parts of the virus. Conclusion: Comparison of the data with previous studies on proliferation of specific lymphocytes in response to rubella vaccination confirms our results. Thus cell-immunity to rubella infection was activated timely, in individuals who were vaccinated against rubella virus approximately 10 years before or exposed to it, but the intensity of responses to different antigens varied in each subject.